Process for making white lead.



J. A. ERBSLOW. rnoc'sss FOR MAKING WHITE LEAD.

APILIOATION FILED SEPT. B. 1908- Patented Aug. 3, 1909.

UNITED STATES PATENT OFFICE.

JOHN A. ERBSLOW, OF LOS ANGELES, CALIFORNIA.

PRocEss FOR MAKING WHITE LEAD.

No. 930,057. Specification of Letters Patent.

Patented Aug. 3, 1909. Application filed September 8, 1908. Serial No. 452,160. I

To all whom it may concern: I zontal. Said vat may be of any suitable Be it known that I, JOHN A. ERBsLOW, a shape, for example cylindrical and may be citizen of the United States, residing at Los g lined with lead, as indicated at 5. The shaft Angeles, in the county of Los Angeles and l 2 is provided with suitable grinding means, State of California, have invented a new and for example, a pulley 7 to receive power for useful Process for Making White Lead, of I rotating said shaft. which the following is a specification. 8 designates a pipe for supplying water to The main object of the present invention is i the vat, the vat being open at its upper end to provide for the roduction of White lead in and the said pipe being located above the an economical and efiicient manner. i open end of the vat.

Another object of the invention is to ro- 9 designates a suction pipe for drawing vide for the production of white lead of defioff the foam. nlte composition and quality. 4 A plurality of the tumbling devices dehe invention relates to the class of proc- I scribed above may be arranged in a series as esses wherein the white lead is produced by shown in Fig. attrition of lead in the presence of Waterand being provided for the series, leading to a of oxidizing and 'carbonating agents, and an suction fan 1]. which discharges onto a drying especial object of the invention is to provide 1 table 12 forming the bottom of a chamber 13. for use of atmospheric air as an ellicient I Said chamber is formed withtwo longitudlnal agent for this purpose. compartments 14, 15 connected at their ends; Another object of the invention in this the conduit from the suction fan dischargmg connection is to provide for separation of the into one of said compartments at 16, See produced white lead free from contamination dotted lines in Fig. 3, and an outlet or d1swith impurities, such as finely divided lead. charge pipe 17 being provided from the other he process consists essentially in tulncompartment. A scraper is provided conbling or otherwise moving load while in a sisting of a series of blades 18 01) 81 611411883 more or less divided. state to cause attrition chain 19, said endless chain being mounted thereof; causing the lead in such motion to l on sprocket wheels 20 carried by vertical pass alternately into contact with the body i shafts 21 mounted in a frame 22, n of Said 2 vertical shafts having suitable driving means I 23, whereby the chain may be made tov continually scrape the material along the floor or table 12 from the inlet to the outlet of the drier. Heating means, for example steam coils 25, are provided to heat the table 12.

pr cess is carried out as follows: The

of Water and with atmospheric air thereby causing continual corrosion of the lead into hydrate and carbonate and attrition oi the lead before or after corrosion; causing the lead in its movement from the atmospheric air into the body of water to carry air into said body of water thereby developing a foam consisting of white leadmixed with atmos- I lead 1s divided to a suitable condition of finepheric air and water, drawing oli' said foam, ness, for exam is by meltin and pouring and drying the foam. i into water to orrn slugs. he lea so d1- The accompanying drawings illustrate an i vided is placed in the vet 1 and the shaft 2 apparatus suitable for carrying out the being set in rotation, vat 1 is turned at such process.

Figure 1 is a front elevation of the complete apparatus. Fig. 2 is a vertical section I the friction of the Walls and the bottom of the vat upwardly at the rising side of thevat, of the tumbling apparatus. Fig. 3 is a horithe lead continually rising at one side and zontal section of the drier. Fig. 4 is a vertifalling as it reaches or passes the mid plane cal section showing a different form of tum- I of the vat, the motion and distribution of the bling apparatus. i lead being somewhat as indicatodat 27 in The tumbling apparatus consists of a tub I Fig. 1; At the same time water is allowed or vat 1 carried by a shaft 2 which is mount- I to flow into the vat lead from the pipe 8, ed to turn on suitable bearings 3 on a base 4, J said water occupying the lowermost part oi the shaft 2 being inclined so that the axis of l the vat, as indicated at 28. The motion of the vat extends at an inclination to the horithe vat is not sufiiciently rapid to cause the veloclty as to cause the lead to be carried by- 1, a common suction pipe 10 being so located and suction bein applied. to this water to partake fully or materially in the circulatory or tumbling motion of the lead, the water remaining for the most part in a body at the bottom of the vat, thus the tumbling action of the lead as it rises at one side of the vat, carriesit out of the water into the atmospheric air in the upper part of the vat and the further motion of the lead as it returns to the lower part of the vat carries it again into the body of water, thus the lead is alternately exposed to contact with water and with atmospheric air. Under these conditions a coating of hydrate and carbonate of leadis continually formed on the surface of each piece of lead and'in the tum bling motionthis coating is continually being ground away. As much of the lead as may be ground off from the pieces of lead before being corroded will eventually become corrode-d by the action of the atmospheric air as the articles of lead. are exposed thereto.

T e continual movement of the lead down into the water from the air, carries the air down into the water and thereby produces a foam 29 consisting of white lead, air and water, which rises to the surface in a bulk light mass. The suction pi )e 9 aforesai as to extend into this mass of foam, pipe, the --foa m is drawn t erethrough and is conveyed by the suction to the dryin table where it is dried by the heat supplier. by the steam coils.

In the practicalcarrying out of the process it is found that the mud formed by attrition of the lead in this manner is more or less colored, presumably by the presence of uncorroded lead, being of a blulsh color.

It is found that while the mud formed in the water is discolored as stated, the product existing in and produced from the foam is substantially pure white. It is obvious that the conditions for oxid ation and carbonation in the foam are more favorable than they are in the body of water, and the corroded lead being lighter than the uncorroded lead, it is apparent that the foam will contain less uncorroded lead than the mud formed in the water. Aside from any ex lanation, however, that may be offered, the results of actual working of the process show that the product pro need by drying the form is substantially white and remains white after mixin with water or oil; whereas, the mud forme( in the water does not become so white on drying and regains its moistening with water or oil. The said mud is'therefore not s itable for use as white lead without further treatment; whereas the product of the ried foam is suitable for use as white lea without further treatment. No grinding is necessary as the product is a substantial y Impalpable )owder.

The apparatms may be variously conthe water and lead and dark color on structed, for example, as shown in Fig. 5 the vat, indicated at 30 may have a plurality of distributing rings 81 extending paralle to the bottom of the vat so as to present an increased frictional surface for ifting and tumbling the lead.

The process is preferably carried out in the presence of atmospheric air, which is found in quantities to furnish sufficient carbon dioxid, as well as oxygen, mixture of carbonate and hydrate. If more carbonate is desired, carbon dioxide gas may be supplied by any suitable means.

What I claim is:-

1. The process of making white lead which consists in causing the lead in divided condition to move alternately into a body of water and into atmospheric air above the body of water, causing the pieces of lead in this motion to rub on one another, and in their descent from the air into the water, to carry air into the body of Water to produce a foam containing white lead, drawing off said foam and drying the foam to obtain the White lead therefrom.

2. The process of making white lead which consists in causing dition to pass alternately into a body of to form a the lead in divided con"- water and of gas containmg carbon dioxid I and oxygen, to cause corrosl n and attrition of the lead and to form a foam containing white lead, drawing off said foam and drying the foam to obtain white lead.

3. The process of making white lead which consists'in causing the lead in divided condition to pass alternately into a body of Water and of gas containing carbon dioxid and oxygen, to cause corrosion and attrition of the lead and to form a foamcontaining white lead, drawing ofi said foam by suction and drying the foam to obtain white lead.

. 4. The process of making white lead which consists in producing a foam by mechanical agitation of lead in the presence of water and air, separating said foam from drying said foam to obtain white lead. I

5. The process which consists in tumbling lead in divided condition in the presence of water and air causing the formation of foam, allowing'said foam to accumulate on top of the water, removing the accumulated foam, and drying the foam to form white lead.

6. The process of making white lead which consists in exposing lead in a divided condition to the action of water and air causing attrition of the lead to produce in connection with the water and the air a foam containing white lead, allowing said foam to accumulate on top of the water, removing the accumulated foam, and drying the foam to obtain White lead.

7. The rocess which consists in exposing Water and air, eainsing attrition of the lead to set mg Hand at Los, Angeles, California, this I producein vconneetion with the water and 31st y of August, 1908. 7 air a foam containing white lead, removing. the foam from the water'and lead by the JOHN ERBSLOW' 5 action of a current of air and drying said In presence of- J foam. ARTHUR P. KNIGHT, In testimony whereof, I have hereunto FRANK L. A. GRAHAM. 

